Control means for sewing machines



May 15, 1951 A. ROTHENBORG ETAL 2,553,211

CONTROL MEANS FOR SEWING MACHINES Filed Jan. 22, 194e z sheets-'sheet 1v Lw/'12u67 May 15, 1951 A. ROTHENBORG ET AL 2,553,211

CONTROL MEANS FOR SEWING MACHINES Filed Jan. 22, 1946 -2 Sheets-Sheet 2Patented May 15, 1951 CONTRL MEANS FOR SEWING MACHINES Aage Rothenburg,Hellerup, Denmark, and Allan Herman Eriksson and Bengt Arne Magnusson,Huskvarna, Sweden, assignors to Husqvarna Vapenfabriks Aktiebolag,Huskvarna, Sweden,

a corporation of Sweden Application January 2.2, 1946, Serial No.642,642 In Sweden December 29, 1944 7 Claims. (Cl. 112-158) In certainkinds of work, such as embroidery work, which are performed by means ofZig-Zag sewing machines, it is desirable that both hands be free as faras possible to keep and guide the work. The present invention has forits object to provide an arrangement facilitating such operations, thesame being devised to permit the performance of certain operatingmovements by the knee of the operator.

A substantial characteristic feature of the invention resides primarilyin the combination of an operating member adapted to be actuated by theknee of the operator with a coupling member adapted to be coupled atwill, to certain operated means, such as the lifting means of thepresser foot, when this is desired, or to means for the control of theneedle bar amplitude, when this is desired. Consequently, the inventionpermits not only the governing of a certain movement with the aid of theknee, but also the selection of an arbitrary one of two or more dierentoperating movements and their coupling to the operating member throughthe actuation of a coupling member. The operating movements primarilybrought into consideration refer to the movement of the presser foot barat the lifting of the presser foot and to the actuation of the zig-Zagmechanism for the control of the width of the zig-zag seam (theamplitude of the oscillatory movement of the needle bar).

Further features characteristic of the invention and advantages inherenttherein will appear from the following description of two embodimentsillustrated in the accompanying drawing, said embodiments being intendedto serve as an elucidating example. The drawing shows parts of a Zig-Zagsewing machine with a device according to the invention mounted thereon,Figs. 1-3 of one embodiment, Fig. l being a front elevation, Fig. 2 aplan view, and Fig. 3 an end view, partly in a vertical cross sectionthrough the housing of the sewing machine, and Figs. 4-7 of the otherembodiment, Fig. 4 showing a iront elevation of a zig-zag sewing machineprovided with the operating device, and Fig. 5 being a vertical sectionon line A-A in Fig. 4. Figs. 6 and 7 show a detail in section on linesC-C and D-D in Fig. 5, respectively. Figs. 8 and 9 are cross sections ofa detail of the control means showing two different positions of theparts.

As shown in Figs. 1-3, the operating member may consist of a bell cranklever 3 provided with a supporting plate I for the knee 2 of theoperator, said bell crank lever being mounted on a` xed stud 4 andconnected with the one end of a CII link rod 5, the other end of whichis pivotally connected to a supporting member or an arm 6 constitutingthe one lever arm of a bell crank lever, the other arm of which isdesignated by '1. The bell crank lever 6, l is mounted concentrically toa shaft 8, preferably on a bearing bushing 9 arranged thereon, saidbushing being fitted into the wall lil of the housing of the sewingmachine. The shaft 8 is coupled, by means of arrangements not shown inthe drawing, to the mechanism effecting the zig-zag movement of thesewing machine, in a manner such that the amplitude of the Zig-Zagmovement or the width of the seam is controlled by a turning movement ofsaid shaft. An example of such a mechanism will be found in theco-pending patent application Serial No. 648,183, iled February 16,1946.

An arm II is mounted concentrically with the shaft 8, preferably on thebushing 9, said arm being connected through a link rod I2' to the onearm of a bell crank lever i5 mounted on a xed stud I4, the other arm ofsaid bell crank lever cooperating with a lifting block I5 coupled to thepresser foot bar I'I.

The operating member may be coupled to the shaft 8 or to the describedmechanism for raising the presser foot bar, said coupling being effectedby means of a coupling member consisting of a carrier I9 mounted on astud I8 in a slot in the arm 1. The carrier i9 is made as a double-armedlever, one arm of which is provided with a carrier abutment Z, which maybe brought into engagement with a recess 2| in a flange 22 secured onthe shaft 8, and the other arm of which has a carrier abutment 23 forcooperation with a slot 24 in the arm I I pertaining to the liftingdevice of the presser foot bar.

The device operates in the following manner:

According to Figs. 3 and 8, the upper arm of the carrier I9 isdepressed, so that the abutment 23 is introduced into the slot 2li ofthe arm II, while the abutment 20 on the lower arm of the carrier is outof engagement with the recess 2| in the flange 22. lf the operatingmember is actuated by the supporting plate I being moved by the knee 2to the left in Fig. l, the rod 5 will be displaced upward by the bellcrank lever 3, so that the bell crank lever 6, 'l is turned in acounter-clockwise direction. The carrier I9 then carries the arm I Ialong with it by means of the abutment 23, said arm then pulling thelink rod I2 to the left, whereby the bell crank lever I5 is turned in acounter-clockwise direction and moves the lifting block I6 so as topress the rod Vhandle 8a in Fig. 5, in such manner that the recess 2| isbrought opposite the abutment 23), whereby the arm 1 is coupled to theshaft .8. At the same time the abutment v23 on the upper arm of thecarrier is moved out of the slot 2'4, so that the connection with thelifting device of the presser bar is interrupted. The shaft 48 can nowbe turned with the aid of the operating device by the supporting platebeing actuated by means Aof the knee, whereby the Width of the seam isvaried.

The invention is not limited to the details illustrated in Figs. 1 to 3,but includes many variations and modifications. For example, a somewhatsimpler construction can be obtained by using the embodiment illustratedin Figs. 4 to y1, in which the coupling member is formed asa linkconnection between the control operating means and -the lever for thepresser foot vlifting member.

As illustrated in Figs. 4 to 6 5 designates the link rod which isincluded in the operating device which comprises a lever system of thetype illustrated in Fig. 1, the upper end of the link rod beingconnected with the one .end of a ldoublearmed lever 6. The lever isymounted concentrically with a regulating shaft 8 pertaining to themeans for regulating the amplitude of the needle bar and the width ofthe seam, said lever being carried on the bushing or sleeve 9 which isrotatably arranged on said shaft and'rotatably fitted into a bearing 41in the wall l0'of the housing of the sewing machine. The presser footbar |'1 may .be raised with the aid of the lever I5' which is pivotallymounted on a stud 15a in the housing of the machine, one arm of saidlever being in engagement with a lifting block I6 arranged on thepresser foot bar. One .end of a link I9' is swingably mounted on a studIB on the upper arm of the supporting member or lever in the figure, theother end of said link forming a connection with one or the other of themembers to be operated, said connection being adapted to be released.`According to the drawing, the link i9 is formed to a hook, which in theposition shown by ifull lines grasps about the projecting end :portionI5b of the Ylever I5', but which is adapted to be swung rearward, .sothat a shoulder I9a on the edgethereof is brought into engagement with aprojection 44 ,on that end of the sleeve 9 which projects from themachine housing (dotted lines in Fig. 4). By the fact that the hook isswung over ,in this manner, the connection of the operatingmemberWiththe pressel` foot bar is interrupted, and ,instead the operatingmember is coupled tothe means for regulating the seam width,

The width of the seam is .regulated .manually by turning the shaft' bymeans of a handle 8a,

when is secured on the shaft L8'. When operation is effected by theknee, the turning movement of the sleeve 9' is transmitted to the shaft8 through a friction coupling consisting of a spring plate li, which :isnon-rotatably secured to the end of the shaft 8 and bears with .its edgeon the end surface of .the sleeve 9'.

A return spring 43 inserted between the bottom of the machine frame, onthe one hand, and a clamping ring 9a surrounding the sleeve, on theother hand, tends to keep the sleeve 9' in an angular position, where apair of abutments 45 on the end of the sleeve 9' are in engagement withcorresponding fixed abutments 46 on the stationary bearing 41surrounding the sleeve. When the link rod 5 is pressed upward by the0perating member, the lever 6 turns about the sleeve 9', so that thelink I9', if coupled to the lever i5', causes the latter to lift thepresser foot bar. On the other hand, if the operating member is actuatedto lift the rod 5, after the link i9 has been swung over into theposition indicated by dotted lines in Fig. 4, wherein the shoulder lSais in engagement with the projection 44, the link I9 will entrain thesleeve, when it is swung by the lever 6 about the center of the shaft8', the spring 43 being thus tensioned. The sleeve 8 entrains .in turn'the shaft .'8' over the friction coupling 40, by means `of .which shaftthe width of the seam is regulated.' After the operating member has beenreleased upon such a movement of adjustment, the sleeve 5' is turnedback into the initial position with the aid `of the return spring 43.

What we claim is:

l. A control means for zig-zag vsewing imachines having a presser foot,a lifting mechanism for the presser foot and an oscillatory needleoperating mechanism, comprising an operating member adapted to beactuated by the knee of the operator, and a coupling member adapted .tocouple the operating member at will alternatively to the presser footlifting mechanism and vto :the needle operating mechanism to enableliftingof the presser foot or adjustment of the needle .amplitude by theknee.

2. A control means forzig-zag sewing machines having a housing, apresser foot, alifting mechanism for the presser foot, an oscillatoryneedle operating mechanism comprising a .shaft journalled in thehousing, an operating member adapted to be actuated by the knee of .theYoperator and comprising a bell crank klever 'jour-V nalled coaxiallyYwith said shaft, .and a :coupling member for cooperation with saidlever to Iconnect the leyer with the presser foot v.lifting mechanism orwith the shaft alternatively at will, whereby the presser foot may beliftedor .the .amplitude of the oscillatory needle may be adjusted atdesired moments.

3. A control means as claimed .in claim 2 'in which the coupling membercomprises acarrier pivoted to the bell crank lever and provided withabutments, and in which a nange is attached to the shaft and has arecess, and the presser vfoot lifting mechanism comprises an armrotatably mounted on the shaft and having a slot .formed therein, one ofsaid abutments beingadapted-to be engaged with the recess and another ofthe abutments being adapted to Vcooperate with'the slot of the arm.

4. An operating device for Zig-zag sewing machines comprising anoperating member adapted to be actuated by the knee of the operator,mechanisms adapted to be operated by said operating member, a couplingmeans adapted to connect the operating member with said mechanismsalternatively at will, said coupling means comprising a supportingmember and a link 4pivoted at one end to said supporting member -a-ndadapted to be engaged selectively with `one of said mechanisms.

5. A control means for zig-zag sewing machines having a housing, apresser foot lifting mechanism comprising a, lever pivoted to thehousing and an oscillatory needle operating mechanism, comprising meansto adjust the amplitude of the needle operating mechanism, said meanscomprising a shaft, a bushing or sleeve rotatably journalled in thehousing and having a projection and means to connect the bushing withthe shaft, an operating device for selective operation of saidmechanisms, said device comprising a supporting member and a hook-shapedlink pivoted to said supporting member at its one end and adapted to beconnected with one end of said lever or to be turned over and disengagedwith said lever end to engage the projection on the sleeve or bushing.

6. A control means as claimed in claim 5 having abutments on therotatable sleeve, corresponding to iixed abutments for determining aninitial position of the operating device, and a restoring springconnected with the sleeve to keep the same resiliently in its initialposition.

7. In a zig-zag sewing machine having a hous- REFERENCES CITED Thefollowing references are of record in the file of this patent:

UNITED STATES PATENTS Number Name Date 608,553 Mack Aug. 2, 18981,823,817 Christensen Sept. 15, 1931

